Difference In Intelligence Quotient Research Articles

Sex and intelligence quotient differences in age of diagnosis among youth with attention‐deficit hyperactivity disorder

AbstractObjectivesAttention‐deficit/hyperactivity disorder (ADHD) is the most common neurodevelopmental condition and is characterized by inattention, hyperactivity, and impulsivity. Research suggests that some populations, such as females and individuals with high intelligence quotients may be a risk for late ADHD diagnosis and subsequent treatment. Our goal is to advance our understanding of ADHD diagnosis, by examining (1) how child sex and cognitive abilities together are related to the age of diagnosis and (2) whether symptom presentation, current internalizing and externalizing symptoms, and demographic factors are related to age of diagnosis.MethodsOur analyses contained children who completed the required tests (N = 568) from a pre‐existing dataset of 1380 children with ADHD from the Province of Ontario Neurodevelopmental Disorders (POND) Network (pond‐network.ca). First, we conducted a moderation analysis with sex as the predictor, cognitive abilities as the moderator, and age of diagnosis as the outcome. Second, we conducted correlation analyses examining how symptom presentation, current internalizing and externalizing symptoms, and demographic factors are related to age of diagnosis.ResultsHigher IQ was related to a later age of diagnosis. Higher hyperactive–impulsive symptoms and externalizing symptoms were related to an earlier age of diagnosis. Internalizing symptoms were trend associated with a later age of diagnosis in girls. Higher socioeconomic status and non‐White maternal ethnicity were related to later age of diagnosis.ConclusionsIQ, sex, ADHD symptomology, internalizing symptoms, externalizing symptoms, and socio‐demographic factors affect the age of diagnosis.

Clinical Analysis of Lacosamide Monotherapy in the Treatment of Self-Limited Epilepsy with Centrotemporal Spikes.

To evaluate the efficacy and safety of lacosamide (LCM) monotherapy in the treatment of self-limited epilepsy with centrotemporal spikes (SeLECTS). In this study, 89 children with SeLECTS who were treated with LCM monotherapy in the Children's Hospital Affiliated to Soochow University from June 2019 to June 2021 were included. Clinical seizures and spike wave index (SWI) on video EEG during slow-wave sleep were evaluated before and after treatment. The role of LCM monotherapy in improving SWI, controlling clinical seizures and improving cognition was analyzed, and corresponding adverse reactions were documented. There were 52 males and 37 females in this group, with an average age of 7.6 ± 2.1 years. The total effective rate was 93.83% and at 18 months of treatment, the cumulative control rate was 85.19%, the retention rate was 91.01% and the effective rate in terms of EEG spike index was 72.92%, all of which showed a high rate; there was no statistically significant difference in intelligence quotient before and after treatment (P > 0.05). In addition, it was found in the study that the earlier the age of onset, the less obvious the improvement in SWI after LCM treatment; the lower the baseline seizure frequency, the more significant the improvement in SWI after LCM treatment. LCM monotherapy had curative effect and adverse reactions for SeLECTS, with no negative impact on cognition. These significant findings indicate that LCM is likely to become a widely prescribed ASM for the treatment of SeLECTS. Meanwhile, the onset age and baseline seizure frequency had certain value in judging prognosis and predicting curative effect.

Heterogeneity of design features in studies included in systematic reviews with meta-analysis of cognitive outcomes in children born very preterm.

Meta-analyses of the voluminous scientific literature on the impact of very preterm (VPT, <32 weeks' gestation) birth on cognition find a marked deficit in intelligence quotient (IQ) among children born VPT relative to term-born peers, but with unexplained between-study heterogeneity in effect size. To conduct an umbrella review to describe the design and methodology of primary studies and to assess whether methodological heterogeneity affects the results of meta-analyses. Primary studies from five systematic reviews with meta-analysis on VPT birth and childhood IQ. Information on study design, sample characteristics and results was extracted from studies. Study features covered study type, sample size, follow-up rates, adjustment for social context, management of severe impairments and test type. We used random-effects subgroup meta-analyses and meta-regressions to investigate the contribution of study features to between-study variance in standardised mean differences (SMD) in IQ between groups. In 58 cohorts (56%), children with severe impairments were excluded, while 23 (22%) cohorts accounted for social factors. The least reported feature was the follow-up rate (missing in 38 cohorts). The largest difference in SMDs was between studies using full scale IQ tests (61 cohorts, SMD -0.89, 95% CI -0.96, -0.82) versus short-form tests (27 cohorts, SMD -0.68, 95% CI -0.79, -0.57). The proportion of between-study variance explained by the type of test was 14%; the other features explained less than 1% of the variance. Study design and methodology varied across studies, but most of them did not affect the variance in effect size, except the type of cognitive test. Key features, such as the follow-up rate, were not consistently reported limiting the evaluation of their potential contribution. Incomplete reporting limited the evaluation of the full impact of this methodological diversity.

Planning processing in ADHD with comorbid reading disabilities is worse than in ADHD: Based on Das-Naglieri Cognitive Assessment System.

ObjectiveTo explore and compare the cognitive processing weakness of children with Attention deficit hyperactivity disorder (ADHD) and comorbid reading disabilities (RD) (ADHD+RD) and children with ADHD only using the Das-Naglieri Cognitive Assessment System (DN:CAS).MethodsEighty-eight children with ADHD who visited the hospital for the first time from September 2021 to November 2021 and had a Full scale intelligence quotient (IQ) of ≥85 on the Wechsler Intelligence Scale for Children revised in China (C-WISC) were selected (Age: 6–12 years; Grade: 2–6). Based on comorbidity with RD and the subtypes of ADHD (e.g., Inattention dominant type, ADHD-I, Hyperactivity/Impulse dominant type, ADHD-H and Combined type, ADHD-C), these children were divided into the ADHD+RD group (n = 30) and ADHD group (n = 58) as well as the corresponding subgroups. Clinical data on gender, age, grade, IQ scores, and DN:CAS processing scores were compared between both groups/subgroups. Spearman's correlation test was used for correlation analysis of results of interest.ResultsNo differences in age, grade, male-to-female ratio, verbal IQ, performance IQ, and full scale IQ were observed between the ADHD+RD group and ADHD group as well as the corresponding subgroups (P > 0.05). Children in the ADHD-C+RD subgroup had lower scores in Planning processing of DN:CAS than those in the ADHD-C subgroup (P = 0.040). However, there were no significant difference between the ADHD-I+RD subgroup and ADHD-I subgroup in Planning scores of DN:CAS assessment; The grade of ADHD-C+RD and ADHD-I+RD subgroups were positively correlated with the Planning scores of DN: CAS (r = 0.599, P = 0.030 and r = 0.508, P = 0.044, respectively). The grade of ADHD-C subgroup was positively correlated with the Planning and Simultaneous processing scores of DN: CAS (r = 0.409, P = 0.042 and r = 0.406, P = 0.044, respectively).ConclusionOur study confirmed that children of ADHD-C with comorbid RD have a more severe Planning processing weakness compared to children with ADHD-C only. Among the children of ADHD-C+RD, ADHD-I+RD and ADHD-C, such a Planning processing impairment may improve with increasing educational skills.

Herpes simplex virus 1 infection on grey matter and general intelligence in severe mental illness

Schizophrenia and bipolar disorder are severe mental illnesses (SMI) linked to both genetic and environmental factors. Herpes simplex virus 1 (HSV1) is a common neurotropic pathogen which after the primary infection establishes latency with periodic reactivations. We hypothesized that the latent HSV1 infection is associated with brain structural abnormalities and cognitive impairment, especially in SMI. We included 420 adult patients with SMI (schizophrenia or bipolar spectrum) and 481 healthy controls. Circulating HSV1 immunoglobulin G concentrations were measured with immunoassays. We measured the total grey matter volume (TGMV), cortical, subcortical, cerebellar and regional cortical volumes based on T1-weighted MRI scans processed in FreeSurfer v6.0.0. Intelligence quotient (IQ) was assessed with the Wechsler Abbreviated Scale of Intelligence. Seropositive patients had significantly smaller TGMV than seronegative patients (642 cm3 and 654 cm3, respectively; p = 0.019) and lower IQ (104 and 107, respectively; p = 0.018). No TGMV or IQ differences were found between seropositive and seronegative healthy controls. Post-hoc analysis showed that (a) in both schizophrenia and bipolar spectrum, seropositive patients had similarly smaller TGMV than seronegative patients, whereas the HSV1-IQ association was driven by the schizophrenia spectrum group, and (b) among all patients, seropositivity was associated with smaller total cortical (p = 0.016), but not subcortical or cerebellar grey matter volumes, and with smaller left caudal middle frontal, precentral, lingual, middle temporal and banks of superior temporal sulcus regional cortical grey matter volumes. The results of this cross-sectional study indicate that HSV1 may be an environmental factor associated with brain structural abnormalities and cognitive impairment in SMI.

No Clinically Relevant Memory Effects in Perinatal Hyperglycemia and Hypoglycemia: A 40-Year Follow-Up of a Small Cohort.

Maternal diabetes mellitus in pregnancy is associated with impairments in memory functions of the offspring in childhood and adolescence but has not been studied in adulthood. The association of perinatal hypoglycemia with memory has not been studied in adulthood either. The combined sequelae of these two risk factors have not been directly compared. We studied general cognitive ability and memory functions in a prospective follow-up of a cohort born in 1971 to 1974. The sample included participants exposed to prenatal hyperglycemia (n = 24), perinatal hypoglycemia (n = 19), or both (n = 7). It also included controls with no early risks (n = 82). We assessed the participants' Intelligence quotient (IQ), working memory, and immediate and delayed recall of both verbal and visual material at the age of 40. We did not find significant differences in IQ or the memory tests between the groups. We did identify an interaction (p = 0.03) of the early risk with the type of digit span task: compared to the controls, the participants exposed to perinatal hypoglycemia had a larger difference between the forward digit span, a measure of attention, and the backward digit span, a measure of working memory processing (p = 0.022). The interaction remained significant when birth weight was controlled for (p = 0.026). Thus, in this small cohort, prenatal hyperglycemia, perinatal hypoglycemia, and their combination appeared relatively benign disorders. The association of these conditions with neurocognitive impairments in adulthood remains unconfirmed. The significance of the working memory difference needs to be verified with a larger sample.

Autism Spectrum Disorder and IQ - A Complex Interplay.

Autism spectrum disorder (ASD) is characterized as a very heterogeneous child-onset disorder, whose heterogeneity is partly determined by differences in intelligence quotient (IQ). Older epidemiological studies suggested that the IQ-related spectrum tends to be skewed to the left, i.e., a larger proportion of individuals with ASD have below average intelligence, while only few individuals with ASD may have an IQ above average. This picture changed over time with broadening the spectrum view. Within the present perspective article, we discuss discrepancies in IQ profiles between epidemiological and clinical studies and identify potential underlying aspects, for example, the influence of external factors such as sample biases or differences in availability of autism health services. Additionally, we discuss the validity and reciprocal influences of ASD diagnostics and IQ measurement. We put the impact of these factors for diagnostic as well as care and support situations of patients into perspective and want to encourage further research to contribute to the conceptualization of “autism” more comprehensively including the IQ as well as to examine broader (life) circumstances, interacting factors and diagnostic requirements of given diagnoses in childhood as compared to adulthood.

Cardiovascular Health at Age 5 Years: Distribution, Determinants, and Association With Neurodevelopment.

BackgroundEarly childhood may represent an opportune time to commence primordial prevention of cardiovascular disease (CVD, i.e., prevention of risk factors onset), but epidemiological evidence is scarce. We aimed to examine the distribution and parental and early life determinants of ideal cardiovascular health (CVH) in children up to 5 years and to compare the level of cognitive development between children with and without ideal CVH at age 5 years.MethodsUsing data from the Etude sur les déterminants pré et post natals précoces du Développement psychomoteur et de la santé de l'Enfant (EDEN) study, a French population-based mother–child cohort study, CVH was examined in children at 5 years of age based on the American Heart Association CVH metrics (ideal body mass index, physical activity, diet, blood pressure, cholesterol and glucose levels, and passive smoking, considered in sensitivity analysis only). Children were categorized as having ideal (five to six ideal metrics) or non-ideal CVH (<5 ideal metrics). Intelligence quotient (IQ) at age 5 years was assessed using the French version of the Wechsler Preschool and Primary Scale of Intelligence.ResultsAmong the 566 children (55% boys), only 34% had ideal CVH. In fully adjusted logistic regression, boys compared to girls (OR = 1.77, 95% CI 1.13–2.78), children with intermediate (1.77, 1.05–2.98) or ideal (2.58, 1.38–4.82) behavioral CVH at age 3 years and children who spent < 30 min/day watching television (1.91, 1.09–3.34) at age 3 years were more likely to have ideal CVH at age 5 years. At age 5 years, there was a significant 2.98-point difference (95% CI 0.64–5.32) in IQ between children with and without ideal biological CVH after adjusting for confounders.ConclusionThis study highlights that only a third of children aged 5 years had ideal CVH and identified modifiable determinants of ideal CVH and is suggestive of an association between CVH and neurodevelopment at a young age.

Impact of Intelligence Quotient (IQ) on Dental Caries amongst Socially Handicapped Orphan Children and Children Living with Their Parents.

ObjectiveTo evaluate the IQ and dental caries status of socially deprived orphan children and compare with children living with their parents.Study designFor comparison, 100 children in age-group 7-11 years, were divided in two groups: 50 orphanage children (orphanage-group) and 50 school-going children living with their families were included (home group). Raven's colored progressive matrices test was used to record the intelligence quotient (IQ) and dental caries status of children was recorded using dmft Index.ResultsThere was statistically significant difference between children with different levels of IQ for both the groups. However, the majority of children who belong to below average IQ score had higher dental caries.ConclusionChildren with better IQ had less dental caries. There was no difference in IQ and DMFT/dmft score between both the genders. The overall DMFT/dmft was high in children living with their parents when compared to orphanage children.How to cite this articleAgarwalla S. The Impact of Intelligence Quotient (IQ) on Dental Caries amongst Socially Handicapped Orphan Children and Children Living with Their Parents. Int J Clin Pediatr Dent 2022;15(S-2):S230-S233.

Prenatal and postnatal exposures to four metals mixture and IQ in 6-year-old children: A prospective cohort study in South Korea.

Humans are exposed to a mixture of metals during their lifetime; however, evidence of neurotoxicity of such mixtures in critical time windows is still insufficient. We aimed to elucidate the associations of four metals mixture across multiple time points with children's intelligence quotient (IQ) in a prospective cohort study. Prenatal exposure and exposure at age 4 and 6years to four types of blood metals, namely lead, mercury, cadmium, and manganese were quantified in 502 pregnant women and their children who participated in the Environment and Development Cohort study. Children' s IQ scores were assessed using the Wechsler Intelligence Scale at age 6. Bayesian kernel machine regression (BKMR), quantile g-computation models, and elastic net (ENET) models were used to assess the associations of their blood metals mixture with IQ scores. Multivariate linear regression models indicated that postnatal blood manganese exposure at the age of 4years was significantly negatively associated with children's IQ [β=-5.99, 95% confidence interval (CI): -11.37 to-0.61]. In the multi-chemical BKMR and quantile g-computation model, statistically significant inverse associations were found between the mixture of prenatal and postnatal metals and children's IQ score (Difference in children' IQ per quartile increase: -2.83; 95% CI: -5.28, -0.38). Interestingly, we found that manganese levels at both age of 4 and 6years were contributing factors to children's IQ in the mixture models, namely, BKMR, quantile g-computation, and ENET models. Multi-pollutant mixtures of prenatal and postnatal exposures to four metals affected child IQ at 6years of age. We found a relationship between manganese exposure at both age 4, and 6years and children's IQ. Additional studies are warranted to confirm these associations and to control the exposure to different metals during pregnancy and preschool childhood.

Cognitive function of children and adolescent survivors of acute lymphoblastic leukemia: A meta-analysis.

Pediatric cancer and its treatment may have an impact on the neurocognitive functions of childhood cancer survivors (CCS). The aim of the present meta-analysis was to compare the intelligence quotient (IQ) scores between CCS of acute lymphoblastic leukemia (ALL) and controls. A comprehensive electronic search identified original research articles that reported scores of the Wechsler Intelligence Scale (WISC; WISC-III, WISC-IV and WISC-R) for children and adolescents, aged 6–16 years at evaluation, survivors of ALL and healthy controls. The included CCS had completed anticancer treatment and were in remission at the time of assessment. A total of 16 studies were included in the meta-analysis, out of 128 extracted studies, and involved a total of 1,676 children and adolescents: 991 CCS (ALL) and 685 healthy controls. Among the studies, a random effects model revealed a moderate estimate of effect size [standardized mean difference (SMD), −0.78; 95% CI, −1.05 to −0.50], indicating that the WISC scores for total IQ were significantly lower in the CCS than in the controls. The mean total IQ range was 85.2–107.2 in the CCS and 88.4–114.1 in the controls. The difference in the mean total IQ between controls and CCS ranged from −13.8 to 20.6. As regards the WISC scores for verbal IQ, 11 studies were included. A random effects model revealed a moderate estimate of effect size (SMD, −0.71; 95% CI, −1.05 to −0.38), indicating that the WISC scores for verbal IQ were significantly lower in the CCS than in the controls. Among the 9 studies that had available data for performance IQ scores, a fixed effect model revealed a moderate estimate of effect size (SMD, −0.80; 95% CI, −1.09 to −0.52), indicating that the WISC scores for performance IQ were significantly lower in the CCS than in the controls. As the survival rates of children and adolescents with ALL are steadily increasing, regular, lifelong follow-up for neurocognitive late effects is imperative in order to improve their education and employment prospects and overall, their quality of life.

Associations between surrounding residential greenness and intelligence quotient in 6-year-old children

BackgroundResidential greenness has been reported to be positively associated with health benefits for children, including improved cognitive function. We investigated the association between the intelligence quotient (IQ) of 6-year-old children in Seoul, South Korea and surrounding greenness currently and during the mothers' pregnancy. We also analyzed whether these effects differed by the type of greenness, such as natural or built greenness. MethodsThis study considered 189 mother-child dyads from the Environment and Development of Children Cohort study, who lived in Seoul during the prenatal period and when the child was 6 years old. We defined surrounding greenness using Landsat image data from Korean Arirang satellite images with buffers within 100 m – 2000 m of the radius of each participant's residential address. We separately analyzed two types of greenness, namely natural and built greenness. The children's IQ (total, verbal, and performance IQ) was measured using the Korean Educational Developmental Institute's Wechsler Intelligence Scale for Children. ResultsPrenatal exposure to built greenness in 500 m and 1000 m buffers was associated with children's total IQ in a full model [difference in IQ (95% CI): 3.46(0.68, 6.24) and 3.42 (0.53, 6.31) per interquartile increase in proportion of greenness]. However, postnatal exposure to built greenness in all buffers was associated in children's total IQ. We found a stronger association between children's total IQ and built greenness rather than natural greenness. ConclusionsWe found that 6-year-old children tended to score higher on total IQ if they lived in greener neighborhoods. The results provide further evidence of the health benefits of greenness and provide support for urban planning and public health to build healthy urban cities for children and pregnant women.

The Subgrouping Structure of Newborns with Heterogenous Brain-Behavior Relationships.

The presence of heterogeneity/subgroups in infants and older populations against single-domain brain or behavioral measures has been previously characterized. However, few attempts have been made to explore heterogeneity at the brain-behavior relationship level. Such a hypothesis posits that different subgroups of infants may possess qualitatively different brain-behavior relationships that could ultimately contribute to divergent developmental outcomes even with relatively similar brain phenotypes. In this study, we aimed to explore such relationship-level heterogeneity and delineate the subgrouping structure of newborns with differential brain-behavior associations based on a typically developing sample of 81 infants with 3-week resting-state functional magnetic resonance imaging scans and 4-year intelligence quotient (IQ) measures. Our results not only confirmed the existence of relationship-level heterogeneity in newborns but also revealed divergent developmental outcomes associated with two subgroups showing similar brain functional connectivity but contrasting brain-behavior relationships. Importantly, further analyses unveiled an intriguing pattern that the subgroup with higher 4-year IQ outcomes possessed brain-behavior relationships that were congruent to their functional connectivity pattern in neonates while the subgroup with lower 4-year IQ not, providing potential explanations for the observed IQ differences. The characterization of heterogeneity at the brain-behavior relationship level may not only improve our understanding of the patterned intersubject variability during infancy but could also pave the way for future development of heterogeneity-inspired, personalized, subgroup-specific models for better prediction.

Intraindividual relative deficits in visual memory to lateralize seizure onset in temporal lobe epilepsy

It is well established that presurgical neuropsychological assessment can assist in lateralizing and localizing focal epileptogenic regions. However, unlike verbal memory impairment, which is a robust and reliable finding in patients with left temporal lobe epilepsy (LTLE), nonverbal memory deficits are less consistently found among patients with right TLE (RTLE). This study aimed to determine whether memory assessment for spatial location in addition to visual content would differentiate patients with RTLE and LTLE. We compared performances between patients with 25 RTLE and 37 patients with LTLE on the Wechsler Advanced Clinical Solutions-Faces (ACS-F) subscales (Faces I, Faces II, Content, and Spatial), verbal–visual memory asymmetry scores, and intelligence quotient (IQ)–visual memory difference scores. Results revealed no significant differences between patients with RTLE and LTLE for any ACS-F memory score. By contrast, groups demonstrated significant differences in memory asymmetry scores (p = .007) and IQ difference scores (p = .006). Thus, visual memory scores in isolation failed to differentiate groups with RTLE and LTLE; however, within-patient differences between visual memory and other cognitive abilities successfully differentiated the groups. These results highlight the importance of using an intraindividual model of neuropsychological assessment to identify relative weaknesses potentially associated with the epileptogenic region.

IQ Difference before and after Temporal Lobe Epilepsy Surgery: First report from Indonesia

Epilepsy is a serious disorder of the brain, affects almost fifty million people in the world. About 40% of the patients finally became refractory to epileptic drugs, especially those with temporal lobe epilepsy (TLE). This refractory condition may cause psychosocial decline, including patient’s intelligence. Surgical therapy has an important role in stopping further damage to brain cells caused by repeated seizures. The elimination of the seizure after surgery will hopefully results in better intelligence score. This study aims to find out the effect ofsurgical therapyin TLE patients after surgery. We were using a Quasi Experimental study with One Group Pre-test and Post-test design. The samples were taken with consecutive sampling method. Subjects were 15 TLE patients who underwent anterior temporal lobectomy and have passed at least one year postoperative period, and also had done an intelligence quotient (IQ) test before surgery. IQ before and after surgery were measured with WAIS and WISC-R method. The statistical tests used were paired t-test. We found the verbal IQ after surgery(98.8±9.88(76-119)) were significantly higher(p=0.01) comparedwithpreoperativeverbalIQ(92.7±9.60(77-113)). On the other hand, performance IQ after surgery (98.2±8.64(82-115)) were higher compared with preoperative performance IQ (96.0±9.39(75-116)) but it was not significant (p=0.5). Total IQ after surgery (97.8 ±7.69(81-107)) also higher compared with preoperative total IQ (93.9±9.28(75-115)) but also not significant (p=0.08). Postoperative verbal IQ improvement was found compared with preoperative verbal IQ.

Relationship between intelligence and posttraumatic stress disorder in veterans

ObjectiveEvaluate the relationships between posttraumatic stress disorder (PTSD) and measures of intelligence in veterans. MethodVeterans (N = 338) who deployed to Iraq and/or Afghanistan were recruited for a VA study on primary blast exposure. PTSD was evaluated using the Clinician Administered PTSD Scale, 5th edition (CAPS-5) and the PTSD Checklist-5. Intelligence was measured using the Wechsler Adult Intelligence Scale, 4th edition and the Test of Premorbid Functioning (TOPF). Validity was assessed with the Medical Symptom Validity Test, b Test, and Structured Inventory of Malingered Symptomatology. Differences in Intelligence Quotient (IQ) estimates between individuals with and without PTSD were evaluated with t-tests. Correlations evaluated associations between symptom burden and intelligence. ResultsOf the seven IQ measures, only the Full Scale IQ score and TOPF Equated scores were significantly lower (but not abnormal) in the lifetime PTSD group. Moreover, these relationships were no longer significant when accounting for multiple comparisons, and symptom/performance validity appeared to better account for those relationships. Current symptom distress was weakly related to several outcomes, but not when using CAPS-5 measures. Neither lifetime nor current PTSD diagnoses were associated with significantly lower IQ scores. ConclusionsThis study did not support prior conclusions that low IQ is a risk factor for developing PTSD. This discrepancy is likely due to the use of ability and symptom validity checks, and sample characteristics (e.g., education). Future research should further evaluate the relationship of symptom distress on intellectual outcomes in combat veteran samples.

Genetic risk for Alzheimer disease in children: Evidence from early-life IQ and brain white-matter microstructure.

It remains unclear whether the genetic risk for late‐onset Alzheimer disease (AD) is linked to premorbid individual differences in general cognitive ability and brain structure. The objective of the present study was to determine whether the genetic risk of late‐onset AD is related to premorbid individual differences in intelligence quotient (IQ) and characteristics of the cerebral white‐matter in children. The study sample included children of the Generation R Study from Rotterdam, The Netherlands. IQ was measured using a well‐validated Dutch nonverbal IQ test (n = 1908) at ages 5 to 9 years. White‐matter microstructure was assessed by measuring fractional anisotropy (FA) of white‐matter tracts using diffusion tensor imaging (DTI) (n = 919) at ages 9 to 12 years. Genetic risk was quantified using three biologically defined genetic risk scores (GRSs) hypothesized to be related to the pathophysiology of late‐onset AD: immune response, cholesterol/lipid metabolism and endocytosis. Higher genetic risk for late‐onset AD that included genes associated with immune responsivity had a negative influence on cognition and cerebral white‐matter microstructure. For each unit increase in the immune response GRS, IQ decreased by 0.259 SD (95% CI [−0.500, −0.017]). For each unit increase in the immune response GRS, global FA decreased by 0.373 SD (95% CI [−0.721, −0.026]). Neither cholesterol/lipid metabolism nor endocytosis GRSs were associated with IQ or cerebral white‐matter microstructure. Our findings suggest that elevated genetic risk for late‐onset AD may in part be manifest during childhood neurodevelopment through alterations in immune responsivity.

Are changes in ADHD course reflected in differences in IQ and executive functioning from childhood to young adulthood?

Attention-deficit hyperactivity disorder (ADHD) is associated with poorer cognitive functioning. We used a developmental, genetically-sensitive approach to examine intelligence quotient (IQ) from early childhood to young adulthood among those with different ADHD courses to investigate whether changes in ADHD were reflected in differences in IQ. We also examined executive functioning in childhood and young adulthood among different ADHD courses. Study participants were part of the Environmental Risk (E-Risk) Longitudinal Twin Study, a population-based birth cohort of 2232 twins. We assessed ADHD in childhood (ages 5, 7, 10 and 12) and young adulthood (age 18). We examined ADHD course as reflected by remission, persistence and late-onset. IQ was evaluated at ages 5, 12 and 18, and executive functioning at ages 5 and 18. ADHD groups showed deficits in IQ across development compared to controls; those with persistent ADHD showed the greatest deficit, followed by remitted and late-onset. ADHD groups did not differ from controls in developmental trajectory of IQ, suggesting changes in ADHD were not reflected in IQ. All ADHD groups performed more poorly on executive functioning tasks at ages 5 and 18; persisters and remitters differed only on an inhibitory control task at age 18. Differences in ADHD course - persistence, remission and late-onset - were not directly reflected in changes in IQ. Instead, having ADHD at any point across development was associated with lower average IQ and poorer executive functioning. Our finding that individuals with persistent ADHD have poorer response inhibition than those who remitted requires replication.

Cognitive and behavioural outcome of children born after IVF at age 9 years.

STUDY QUESTIONDo ovarian stimulation (OS) and the in vitro laboratory procedures affect offsprings’ cognitive and behavioural outcome at 9 years?SUMMARY ANSWEROS and the in vitro laboratory procedures or the combination of both were not associated with cognitive and behavioural outcome at age 9 years.WHAT IS KNOWN ALREADYART is not associated with an adverse short-term developmental outcome of the offspring, but limited knowledge is available on the offspring’s long-term neurodevelopmental condition.STUDY DESIGN, SIZE, DURATIONA 9-year longitudinal, assessor-blinded, prospective follow-up study of 169 out of 215 singletons (79%) born between March 2005 and December 2006 was performed.PARTICIPANTS/MATERIALS, SETTING, METHODSSingletons born following IVF or ICSI with OS (n = 57), born after modified natural cycle IVF/ICSI (MNC-IVF/ICSI; n = 46) and born after natural conception to subfertile couples (Sub-NC; n = 66), were assessed at 9 years. This study design, with two ART groups and a subfertile reference group, allows for disentangling the effects of OS and ART procedures on developmental outcome. Cognitive outcome was evaluated with the Wechsler abbreviated scale of intelligence and the NEPSY-II. Behaviour was assessed with the child behaviour checklist (CBCL) and teacher report form (TRF). Univariable analyses and multiple linear regression models were used.MAIN RESULTS AND THE ROLE OF CHANCEThere was no significant difference in intelligence quotient (IQ) scores between ART groups (mean IQ (95% CI): OS 114.8 (83.2–142.6); MNC 114.0 (90.2–140.8); Sub-NC 115.4 (87.9–141.2), P = 0.746). Multivariable analyses did not reveal a statistically significant association between ART group and total, verbal and performance IQ. CBCL and TRF scores did not differ significantly between ART groups (P = 0.090 and 0.507, respectively). Multivariable analyses did not demonstrate a statistically significant association between ART group and CBCL and TRF total, or internalising and externalising T-scores. No significant correlations between time to pregnancy (TTP)—a proxy for the severity of parental subfertility—and outcome measures were found (Spearman rho between −0.050 and 0.049, NS), which was confirmed with multivariable analyses.LIMITATIONS, REASONS FOR CAUTIONThe attrition rate of 21% may be considered as a limitation of the study; however, after a follow-up period of 9 years, this rate is generally considered acceptable, and there were no significant differences in background characteristics between children with and without follow-up, making an attrition-related selection bias less likely. Another limitation of the study is the relatively small sample size, which could contribute to selection bias, hamper generalizability to the ART population and lead to false negative findings as a result of underpowering. An a priori power analysis on total IQ indicated that the OS-IVF/ICSI and Sub-NC groups should contain 64 children, confirming that our study including 57 and 66 children, respectively, was slightly underpowered.WIDER IMPLICATIONS OF THE FINDINGSOur study indicated that OS and the in vitro laboratory procedures or the combination of both and TTP were not associated with cognitive and behavioural outcome at 9 years. These are reassuring results for both parents and clinicians involved in ART.STUDY FUNDING/COMPETING INTEREST(S)The study was financially supported by the University Medical Center Groningen (UMCG), two graduate schools of the UMCG (BCN and SHARE) and the Cornelia Stichting. The sponsors of the study had no role in study design, data collection, data analysis, data interpretation or writing of the report. The authors have no conflicts of interest to declare.

MACHINE LEARNING IN PSYCHIATRIC GENOMICS: INTEGRATING MULTIPLE LEVELS OF ANALYSIS THROUGH DEEP NETWORK MODELS

Schizophrenia patients (SCZ) display widespread cognitive deficits that are strongly associated with functional outcomes. Cognitive impairments occur along a genetic continuum among SCZ, their unaffected first-degree relatives (FRs) and healthy controls (HCs). Although SCZ impairs the premorbid intelligence quotient (IQ) and causes a subsequent intelligence decline (ID), a decrease in present IQ from the premorbid level, it remains unclear when during the illness course these impairments develop. Differences in premorbid and present IQ and ID were investigated among 125 SCZ, 61 FRs and 107 HCs, using analysis of covariance and a paired t-test. Furthermore, these subjects were classified into preserved and deteriorated IQ groups based on the degree of ID, and we investigated which factors contribute to this classification. We found significant differences in premorbid and present IQ among the diagnostic groups. Compared with HCs, SCZ and FRs displayed lower premorbid and present IQ. There was no significant difference in premorbid IQ between SCZ and FRs, but SCZ had a significantly lower present IQ than FRs. Only SCZ showed a significant ID. As most FRs and HCs did not display an ID, there were fewer subjects with deteriorated IQ among FRs and HCs than among SCZ. Subjects with preserved IQ showed higher educational attainment than those with deteriorated IQ among SCZ and FRs. These findings suggest that the impairment of premorbid IQ and the ID in SCZ become evident before and around the time of onset, respectively, and different pathophysiological mechanisms might be related to these impairments.